1. Technical Field
The present invention relates to a light transmissive member, a timepiece using the light transmissive member as a cover glass, and a light transmissive member production method.
2. Related Art
It is known that in order to enhance the visibility of the display of time or the like, an antireflection layer is formed on a light transmissive member called “cover glass (windscreen)”. This antireflection layer is generally constituted by stacking several to several tens layers of inorganic layers having different refractive indices, and in the case where a high hardness and scratch resistance are required for the surface of the cover glass, silicon oxide (SiO2) having a high light transmittance, a low refractive index, and a relatively high hardness is often deposited on the outermost layer of the antireflection layer. For example, JP-A-2004-271480 (Patent Document 1) discloses a technique for forming an antireflection layer, in which silicon oxide is used as the outermost layer and the lowermost layer, and a silicon oxide (SiO2) film and a silicon nitride (Si3N4) film are alternately stacked, on the surface of a substrate for a cover glass for a timepiece.
However, in the light transmissive member having the antireflection layer disclosed in Patent Document 1, although the visibility can be improved, the antireflection layer is relatively easily electrified, and therefore, has a problem that foreign substances are adhered to the surface by electrification due to static electricity or the like, and a defect such as deterioration of visibility or appearance may occur.